The number of items in a carton depends on the size of the carton. What is the independent variable and dependent variable?

Rachel reads 1/5 of the pages of a book plus 12 pages on the first day. on the second day, she reads 1/4 of the remaining pages plus 15 pages. on the third day, she reads 1/3 of the remaining pages plus 18 pages. on the fourth day, she reads the remaining 70 pages. how many total pages are in the book?

36 inches/second = yards/minute how many yards?

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?